Units for enhancing display of various displayable materials are well known and/or utilized and include units for back-lighting of such materials.
In particular light-boxes having displayable material on one face thereof and employing reflectors and light sources within the box to achieve back-lighting are known and/or utilized. One such arrangement, for example, is described in U.S. Pat. No. Re. 24,728 to R. DeMontbello issued Oct. 27, 1959 wherein a concave reflector is used for reflecting light from a light source to back-light various displayable material, a focal axis of the curved reflector being formed at the midportion of the curved reflector requiring a deeper curve as the area to be illuminated grows.
A second lighting arrangement is shown, for example, in U.S. Pat. Nos. 1,320,537, issued Nov. 4, 1919 to C. W. Diamond, and 2,297,851 issued Oct. 6, 1942 to Wyss, Jr. As described therein, a reference surface is illuminated by use of a reflector and light source beneath (or channeled beneath) the surface, the reflector being parallel to the surface throughout most of its length and curving toward the surface only at the end thereof.
A third example of a lighting arrangement is shown in U.S. Pat. No. 2,487,403 issued Nov. 8, 1949 to R. I. Wisdom. As described in this patent, the device employs a convex reflector behind the surface to be illuminated which is disposed along a portion of the rear wall of a light-box.
Thus, while units for enhanced lighting of various surfaces have heretofore been suggested and/or utilized, further improvement could nevertheless still be utilized.